On the physics of upgradient momentum transport in unstable eastward jets
- 1 September 1998
- journal article
- research article
- Published by Taylor & Francis in Geophysical & Astrophysical Fluid Dynamics
- Vol. 88 (1-4) , 295-323
- https://doi.org/10.1080/03091929808245478
Abstract
The weakly nonlinear finite amplitude evolution of mixed baroclinic/barotropic instabilities of an eastward zonal jet is considered in a two-layer QG-model on a mid-latitude beta-plane. Linear friction is included and is essential to the momentum transport. The focus is two parameter regimes, one corresponding to the Gulf Stream and the other to the Antarctic Circumpolar Current. In the latter case, the nonlinear self-interaction of the most unstable mode causes upgradient momentum transport and therefore sharpens the jet. The analysis of this example leads to a clear description of the physics of this process. It also indicates why upgradient momentum transport does not occur in the Gulf Stream regime.Keywords
This publication has 12 references indexed in Scilit:
- Sideband instabilities of mixed barotropic/baroclinic waves growing on a midlatitude zonal jetPhysics of Fluids, 1997
- Potential Vorticity Constraints on the Dynamics and Hydrography of the Southern OceanJournal of Physical Oceanography, 1993
- On the Existence of Storm-TracksJournal of the Atmospheric Sciences, 1990
- Geophysical Fluid DynamicsPublished by Springer Nature ,1987
- The physics of the Antarctic Circumpolar CurrentReviews of Geophysics, 1986
- A theoretical discussion of eddy-driven mean flowsDynamics of Atmospheres and Oceans, 1979
- A description of numerical antarctic circumpolar currentsDynamics of Atmospheres and Oceans, 1978
- Momentum Transport by Quasi-Geostrophic EddiesJournal of the Atmospheric Sciences, 1975
- Finite-Amplitude Baroclinic WavesJournal of the Atmospheric Sciences, 1970
- Baroclinic instability in two layer systemsTellus, 1963